The invention concerns a valve system with at least one valve body and a longitudinal slide slidably disposed therein which establishes or disrupts a connection between a feed line and at least one inlet or outlet in the valve body, and having an electrochemically driven actuator that displaces the longitudinal slide.
Such valve systems are known internally, for example for applications in petroleum or natural gas extraction or the like. Depending on the position of the longitudinal slide, a feed line having an inlet or outlet for a hydraulic fluid is connected by valve bodies and longitudinal slides movably disposed therein. An actuation device is provided with hydraulic fluid via the feed line, this actuation device being used, for example, for adjusting a throttle, for actuating a so-called blowout preventer for actuating a valve, or the like.
In order to be able to operate and control this valve body and longitudinal slide of the valve system precisely and reproducibly, it has already been proposed that electrical actuation be performed instead of pneumatic or hydraulic actuation of the valve system. Such an electric actuation takes place, for example, via electromagnets or the like. Of course, such electromagnets often lead to considerable heat development, are very heavy, and require some expense for the control. Therefore it was proposed that the longitudinal slide be moved by means of an electrochemically operated actuator.
In the case of an electrochemically operated actuator a gas, and in particular hydrogen, is generated by electric charge in an expandable piece. This causes an over-pressure in the body, which leads to the expansion thereof and correspondingly to the actuation thereof. In order to make the motion of the longitudinal slide and correspondingly the expansion of the body of the actuator retrogressive, it is advisable to discharge the actuator via a resistor. Thus the hydrogen is consumed within the actuator and the pressure is reduced.
Such an electrochemically operated actuator is very small, light, and reliable. In addition, such an electrochemically operated actuator is very high in its positioning accuracy with respect to the longitudinal slide and requires no energy for maintaining the longitudinal slide in a specific position.